US Secretary of State Condoleezza Rice will make a statement on the row over reported secret CIA prisons when she visits Europe next week.
The Minister for Foreign Affairs, Dermot Ahern, said after talks with Ms Rice in Washington that she gave him categoric assurances that Shannon Airport had not been used for 'untoward' purposes as a transit point for terror suspects.
A report in the New York Times newspaper has claimed that some 33 CIA flights have gone through Shannon over the past four years.
Mr Ahern said the Secretary of State told him she would answer a formal query from the EU on reports of clandestine interrogation centres in Europe.
The Bush administration has been under increasing pressure to explain its tactics against detainees.
Mr Ahern said Ms Rice had repeated assurances by US diplomats that Shannon had not been used for renditions - movement of detainees.
Media reports say dozens of US-run flights have used the airport for unexplained reasons, raising speculation they could be transporting militant suspects.
The US, whose security forces have abused detainees in Iraq, says renditions are legal. Human rights groups question that interpretation of international law and say incommunicado detention can lead to torture.
Allegations of renditions and a newspaper report that the CIA has run secret prisons in Europe have fueled widespread concern in the region over US abuses in its war on terrorism.
A new report today, in the French newspaper Le Figaro, says aircraft hired by the CIA and possibly used to transport prisoners have made at least two stopovers in France, in 2002 and 2005.
The conservative newspaper said the first flight was that of a Learjet which landed in Brest after arriving from Keflavik in Iceland on 31 March 2002 and took off again for Turkey.
The second flight arrived at Paris Le Bourget airport from Oslo on 20 July this year.
British newspaper The Guardian said yesterday it had seen navigation logs showing that more than 300 flights operated by the CIA had passed through European airports.
The EU has threatened sanctions against any member state found to have been allowing its territory to be used for the transport of detainees.
